Let-off mechanism for looms



Aug. 9, 1927. 1,638,497

w. J. LUTTON LET-OFF MECHANiSM FOR' LOOMS Filed March 5, 1926 5 Sheets-Sheet l INVENTOR ATTORNEYS 1,638,497 1927- w. .1. LUTTON' LET-OFF MECHANISM FOR Looms Fi led'march 5, 1926 3 Sheets-Sheet 2 ATTORN EYS Aug. 9, 1927. 1,638,497

W. J. LUTTON LET-OFF MECHANISM FOR LOOMS Filed March 5, 1.826 5'ShGGtS-Sh68t 3 I ATTORNEYS Fatented Aug. 9, 1927.

UNITED, STATES if ILLIAMJ. LUTTON, OF PATERSQN, NEW

LE'I OFF' MECHANISM F011 .LUQMS.

Application filed, March 5, $23.; 6rial iflo. 2,5?f1

This invention relates to let-off mechanism for looms, with theobject inview of pro viding means for automatically maintaining v a uniform tension on the I warp threads throughout the entirewidth olfthe shed as the threads are let off step by step from the warp beam.

Another object is to provide 'means for mounting a warp beam which may be moved vertically in the frame of the loom, whereby the weight of the warp beam will apply tension to the warp threads.

Another object is to provide a vertically movable warp beam arranged to receive a weight bar for applying additional weight to the beam and tension to the warp threads.

Another object is to provide mechanism frictionally engaging the warp beam for ar resting the rotary movement thereof, and means controlled by the vertical movement of the beam for releasing said mechanism.

Another object is to provide a manually operated device for temporarily supporting the warp beam and thereby relieving the tension on the warp threads at any moment when it is so desired.

Another object is to provide certain im provements in the form, construction and arrangement of the several parts, whereby the above named and other objects may effectively be attained.

A practical embodiment of my invention is represented in the accompanying drawings, in which Fig. 1 represents a plan view of so much of a loom as is required to illustrate an embodiment of my invention.

Fig. 2 represents an end same.

Fig. represents a vertical section taken in. the plane of the line TIL-Ill of Fig. 2, looking in the direction of the arrows.

Fig. 4: represents a side elevation of the parts shown in Fig. l.

Fig. 5 represents a detail vertical section taken in the plane of the line VV of Fig. i, looking in the direction of the arrows, and

Fig. 6 represents a detail vertical section taken in the plane of the line VI-VI of Fig. 2, looking in the directionof the arrows.

The frame of the mechanism is denoted by 1 and provided with flanges 2 by which it. may be secured to the frame 3 of the loom by bolts 4. A warp b6fl-I11'5 is supported on a shaft 6 journaled in hangers .7, 8 adjustelevation of the ably mounted on arms 9, 10 of a yoke 11. This yoke 11 has reduce'd ends 12, 13 arranged to be journaleddn bearings. 14, 15 fixed to the framel'; The hanger .7 is provided with an elongated slot l G arranged to receivea bolt 17 carried by the arm 9 of the yoke, and lby w h ich bolt the hanger may be adjusted vertically and secured to the arm The lower end of the hanger 7 has an open bearing 18 arranged to receive one end of the shaft 6 of the warp beam;

The hanger 8 is similarly provided with an elongated slot 19, and the arm 10 with a bolt 20, which secures the hanger 8 in vertical adjustment on the armfl The lower end of the hanger 8 also has an open bearing 21 arranged to receive the opposite end of the shaft 6 of the warp beam. I i

The shaft (3 of the warp beam is extended a distance beyond the bearings 18, 21 of the hangers 7., 8 so that a weight bar 22 may be suspended therefrom by means of links 23 24; This weight bar 22is arranged to re% ceive a series of weights 25, the number of weights located on the bar being dependent upon the tension which is desired to be placed upon the warp threads.

The warp beam 5 includes mechanism for arresting the rotary movement thereof which mechanism comprises a drum 26 and two U-shaped straps 27, 2S. Oneend of the strap 27 has a short extension 29 while the other end has a long extension 30. Thestrap 28 alsohasa short extension 31 and a longextension The short extensions 29 and 31 are held in position by means of a bolt 33 and nut 34s. The long extension is arranged to be brought toward the extension by means of an eccentric cam 35 having a shaft 36 journaled in. bearings 3'7, 38 secured to the extension 32 by a bolt 39; The'cam 35 is oscillated by means of an. arm 40 fixed to the shaft 36.

A spring ll is disposed between the arm 40 and a pin 4:2 carried by a bracket 43 secured to the arm 10 of the yoke. This spring a1 tends to pull the arm a0 upwardly so that the cam will force the extension 30 toward extension 32, which movement of the extension will cause the linings 44, so, of leatheror other suitable inaterial,.fir.ed to the straps 27, 28, to frictionally engage the drum 26 and hold the warpbeam against rotation.

The arm a0 is limited in its'movement by means of a lug 46 which extends laterally from the arm -ll) into position to engage the frame 1.

Fixed to rotate with the warp beam 5 is a brake drum 4L7. A. hand brake 4-8 of leather or other suitable material. is seci'n'ed to one end of a bar 4-9 and after passing around the drum M, the opposite end is attached to a bolt 50, the threaded end of which extends through a hole in the bar 4-9 and is provided with nuts 51, 52 for adjusting the frictional contact of the brake -18 on the drum 47.

"the warp beam 5 together with. the yoke and weight bar with the weights thereon may be sustaini-zd at any time in the desired iievtion by means of a link 52-}, one end of wi 'rh is pivoted at 5 .1: to the end of the arm 9 of the yoke, while the other end of the link has a bolt 55 arranged to extend through a slot 56 in the frame 1. The threaded end of the bolt is provided with a tail nut 5i which serves to draw and lock the link 53 and frame together, thereby securing the arm 9 of the yoke against movement. By locking the arm 9 to the frame the weight of the Warp beam and its adjacent mechanism on the warp threads 58 is relieved.

The warp threads 58 carried by the warp beam 5 are arranged to pass upwardly over the warp guide roller 59 journaled in uprights 60, (31, adjustably mounted on the frame 1. by means of bolts 62, 63. The warp threads pass from the guide roller 59 over and under spreaders (i l, 65 through the usual heddles and reeds (not shown).

The outer end'of the extension 32 is disposed in position to bear upon the yoke 11 and hold the straps 2T, 28 against rotation on the drum 26 of the warp beam 5.

The outer end of the brake band &8 is also arranged to rest upon the yoke to pre- .vent the same from rotating with the drum on the warp beam 5.

llhile I have only shown a link 53 connected to the arm 9 of the yoke 11 and carrying a. bolt 55 and tail nut 57 arranged to slide in a slot 50 of the frame 1 to hold the beam and its mechanism against movement, i wish it understood that the arm 10 may also be provided with a similar link and bolt arranged to slide in a slot 66 in the frame 1.

In operation, assuming the warp beam has been secured in the arms 9, 10 of the yoke 11, the necessary number of weights 25 added to the weight bar 22, the brake band 48 and straps :27, 28 adjusted and placed under such restraint found desirable, the weaving will gradually lift the warp beam 5 and its weights together with the arms of the yoke the warp threads are taken up. This upward movement of the warp beam 5 will bring thelug lti on the arm 40 into engagement with the frame 1, whereupon the further pward nn'ivernent ol' the beam will hold the arm 40 and cause the cam 55 to change its position with respect to the extension 30 of the strap 27. As the cam 35 changes its position, the exension 30 will be free to move. away from the extension 32 of the strap 28, which movement will release the frictional contact of the straps 27, 28 on the drum 26, and in consequence thereof the beam, due to its weight, will begin to swing downwardly by gravity and rotate to :let oti the warp threads wound thereon.

This downward movement of the beam will continue until the lug -16 has been moved away from the frame .1. so that the spring ll may exert its power to rock the arm a0 and hence the cam 35. In rocking the arm and cam, the extension 30 will be again forced toward the extension 32 and the straps 27, 28 caused to grip the drum 26, which thereby arrests the rotary'as well as the downward movement of the beam. It will be understood that the link 53 will also move with the arm 9 and the bolt 55, carried by the link 53, will be free to slide in the slot 56 in the frame, and at any time the warp beam and its adjacent mechanism may be held in the desired position by screwing the tail nut 57 on the bolt 55 which will draw the link 52:3 against the frame 1 and lock the same against movement. By locking the link to the frame, the yoke with its arms and beam will be held against movement, in

which position the tension on the warp threads will be relieved. V

The tension on the warp threads may be reestablished and the parts again resume their respcctivepositions by un-screwing the tail nut on the bolt, thereby releasing the link. When the link and boltare released the mechanism is free to be actuated by ihe weaving operation. I

It is obvious that various changes may be resorted to in the form, construction and arrangement of the several parts without departing from the spirit and scope of my invention; and hence, I do not intend to be limited to the particular embodiments herein shown and described except as they may be included in the claims. V

What I claim is:

1. In a loom, a frame, a warp beam vertically movable in said frame, mechanism frictionally engaging said beam for arresting the rotary movement thereof, and means for releasing said mechanism, said means normally engaging the mechanism for bold ing the beam and arranged to be brought into contact with the frame for actuating it by the vertical movement of the beam.

2. In a loom, a frame, a warp beam vertically movable in said frame, mechanism frictionally engaging said beam for arresting the rotary movement thereof, means for releasing said mechanism, said means normally engaging the mechanism for holding the beam and arranged to be brought into contact with the frame for actuating it by the vertical movement of the beam, and a spring coacting with the means for returning it to its normal position and actuating the mechanism to arrest the rotarymovement of the beam.

3. In a loom, a frame, a yoke pivotally mounted therein, a Warp beam carried by said yoke, said beam being arranged to carry and apply tension to the warp threads, mechanism frictionally engaging the beam for arresting the rotary movement thereof, and means for releasing said mechanism, said means normally engaging the mechanism for holding the beam and arranged to be broughtinto contact with the frame for actuating it by the vertical movement of the beam.

4. In a loom, a frame, a yoke pivotally mounted therein, a warp beam carried by said yoke, said beam being arranged to carry and apply tension to the warp threads, mechanism frictionally engaging the beam for ar resting the rotary movement thereof, means for releasing said mechanism, said means normally engaging the mechanism for holding the beam and arranged to be brought into contact with the frame for actuating it by the vertical movement of the beam, and a spring c-oacting with the means for returning it to its normal position and actuating the mechanism to arrest the rotary move ment of the beam.

5. In a loom, a frame, a yoke pivotally mounted therein, a warp beam carried by said yoke, said beam being arranged to carry and apply tension to the warp threads, mechanism frictionally engaging the beam for arresting the rotary movement thereof, means for releasing said mechanism, and a device coacting with the frame and yoke for temporarily locking the yoke to the frame thereby supporting the beam and relieving the tension on the warp threads.

6. In a loom, a frame, a yoke pivotally mounted therein a warp beam carried by said yoke, said beam being arranged to carry and apply tension to the warp threads, mechanism frictionally engaging the beam for arresting the rotary movement thereof, means for releasing said mechanism, and a manually operated device coacting with the mechanism frictionally engaging the beamfor arresting the rotary movement thereof, and means for releasing said mechanism, said means comprising a cam carried by and dis posed to engage the mechanism, and an arm on said cam arranged to be brought into contact with the frame for actuating the cam to release the mechanism.

8. In a loom, a frame, a yoke pivotally mounted therein, a warp beam carried by said yoke, said beam being arranged to carry and apply tension to the warp threads, mechanism frictionally engaging the beam for arresting the rotary movement thereof, and means for releasing said mechanism, said means comprising a cam carried by and disposed to engage the mechanism, and an arm on said cam arranged to be brought into contact with the frame for actuating the cam to release the mechanism, the movement of saidarm being controlled in one direction by the vertical movement of the beam.

9. In a loom, a frame, a yoke pivotally mounted therein, a warp beam carried by said yoke, a weight bar suspended from said beam for applying tension to the warp threads, mechanism frictionally engaging the beam for arresting the rotary movement thereof, and means arranged to be brought into contact with the frame for releasing said mechanism.

10. In a loom, a frame, a yoke pivotally mounted therein, a warp beam carried by said yoke, a weight bar suspended from said beam for applying tension to the warp threads, mechanism frictionally engaging the beam for arresting the rotary movement thereof, and means arranged to be brought into contact with the frame for releasing said mechanism, said means being controlled in one direction by the vertical movement of the beam.

In testimony, that 'I claim the foregoing as my invention, I have signed my name this 2nd day of March, A. D. 1926.

WILLIAM J. LUTTON. 

